Annular aerosol jet deposition using an extended nozzle

Abstract

Method and apparatus for improved maskless deposition of electronic and biological materials using an extended nozzle. The process is capable of direct deposition of features with linewidths varying from a few microns to a fraction of a millimeter, and can be used to deposit features on targets with damage thresholds near 100° C. or less. Deposition and subsequent processing may be performed under ambient conditions and produce linewidths as low as 1 micron, with sub-micron edge definition. The extended nozzle reduces particle overspray and has a large working distance; that is, the orifice to target distance may be several millimeters or more, enabling direct write onto non-planar surfaces. The nozzle allows for deposition of features with linewidths that are approximately as small as one-twentieth the size of the nozzle orifice diameter, and is preferably interchangeable, enabling rapid variance of deposited linewidth.

1. An apparatus for depositing a material on a target, said apparatus comprising:
 a device for aerosolizing the material; 
 a deposition flowhead comprising an input connected to said device and an output, said flowhead forming a combined flow comprising an annular sheath gas surrounding and focusing said aerosolized material and outputting said combined flow through said output; 
 an extended nozzle attached to said output of said deposition flowhead, said extended nozzle comprising an interior passage for transporting said combined flow which is tapered along substantially the entire length of said extended nozzle; and 
 no more than one orifice for narrowing said combined flow sufficiently to form a deposited feature comprising a feature size of less than one millimeter on the target; 
 wherein said extended nozzle is of sufficient length to reduce a diameter of said combined flow to less than a diameter of said orifice beyond said orifice. 
 
     
     
       2. The apparatus of  claim 1  wherein an annular gas flow is developed within said deposition flowhead and passed through said extended nozzle. 
     
     
       3. The apparatus of  claim 2  wherein said annular gas flow comprises an outer sheath flow and an aerosol-laden inner flow. 
     
     
       4. The apparatus of  claim 1  wherein said extended nozzle increases the working distance. 
     
     
       5. The apparatus of  claim 4  wherein the target is at least several millimeters from said extended nozzle. 
     
     
       6. The apparatus of  claim 4  wherein the material is depositable into recessed features of the target. 
     
     
       7. The apparatus of  claim 1  wherein said extended nozzle is detachable from said flowhead. 
     
     
       8. The apparatus of  claim 7  wherein said extended nozzle is reattachable to said flowhead without requiring realignment. 
     
     
       9. The apparatus of  claim 7  wherein said extended nozzle is interchangeable with a second nozzle comprising a different exit orifice diameter. 
     
     
       10. The apparatus of  claim 1  wherein said extended nozzle comprises a variable exit orifice diameter. 
     
     
       11. The apparatus of  claim 1  wherein said extended nozzle comprises a material selected from the group consisting of alumina, ceramic, metal, tungsten carbide, and ceramet. 
     
     
       12. The apparatus of  claim 1  wherein said extended nozzle is tapered. 
     
     
       13. The apparatus of  claim 12  wherein said extended nozzle comprises an aspect ratio of between approximately 4:1 and approximately 10:1. 
     
     
       14. The apparatus of  claim 1  wherein said extended nozzle comprises a length between approximately 0.95 centimeters and approximately 1.9 centimeters. 
     
     
       15. The apparatus of  claim 1  wherein said extended nozzle comprises an exit orifice diameter between approximately 50 microns and approximately 500 microns. 
     
     
       16. The apparatus of  claim 15  wherein said exit orifice diameter is 150 microns. 
     
     
       17. The apparatus of  claim 15  wherein said exit orifice diameter is 100 microns. 
     
     
       18. The apparatus of  claim 1  wherein a linewidth of deposited material comprises a size between approximately one-twentieth and approximately one diameter of an exit orifice of said extended nozzle.